1. Field of the Invention
The invention relates generally to telecommunications and more particularly to a communication terminal capable of simultaneously transmitting voice and graphical representations.
2. Description of the Prior Art
In the field of voice and graphical communications, communication terminals are employed to transmit and receive voice and graphical information. In order to transmit and receive voice and graphical information, the communication terminal must be capable of processing voice communications and include a visual display unit for presenting graphical information.
In the past, such a communication terminal was disclosed in German Pat. DE-OS No. 24 33 667. This communication terminal was conventional in that a cathode-ray storage tube was employed as the display screen. The cathode-ray storage tube was intended as an attachment to a first channel in existing telephone equipment for processing voice communications. A second channel in the existing telephone equipment was employed for transmitting graphical representations. Another example of a communicaton terminal is a time work station capable of transmitting voice and graphical information via a common transmission line. Such a terminal was described in "The Electrical Communication Laboratories, NTT, Technical Publication," No. 282, June 1983. This terminal included a telephone set employed for initially establishing a connection and for processing voice communications. The terminal further included an input unit and a visual display unit for processing and displaying graphical presentations.
It is desirable to incorporate the voice communication and graphical presentation functions of a communication terminal into a single unit having a visual display unit for displaying the transmitted information. Both of the aforementioned communication terminals include a separate unit each for the voice communication function and the grpahical presentation function. Problems are associated with the construction of the prior art communication terminals. A first of these problems involves a higher technical investment requiring additional detail to coordinate separate units. A second problem is the larger space requirement for separate units while a third problem is the requirement that each separate unit be individually operated.
After consideration of the known prior art relevant to the instant invention, the aforementioned problems continue to exist.